These CCTV cameras can be mounted on vehicle dashboards or can be body worn usually clipping on to the officers jacket or over there ear
. If police officers are monitoring town and city centers on a busy saturday night there can be so many people around and so much activity that even witnessing an incident first hand such as a group assault it may be hard to recollect exactly what occurred. So for this reason there body worn surveillance as well as the street CCTV cameras are heavily required when reviewing an incident. They also use this footage to help train officers who do not have experience of situations such as dawn raids or an armed seige.